Impulse fuel feeding device



Nov. 6, 1934. E. A. ROCKWELL IMPULSE FUEL FEEDING DEVICE.

Or'fginal Filed Sept, 3, 1927 INVENTOR v Ian 11w 3 m:

ATTORNEY'Z Patented Nov. 6, 1934 UNITED STATES IMPULSE FUEL FEEDING DEVICE Edward A. Rockwell, Long Island City, N. Y.

Original application September 3, 1927, Serial No. 217,422. Divided and this application December 17, 1928, Serial No. 326,688

1 Claim.

This application is a division of my co-pending application for patent on impulse fuel feeding device, Serial No. 217,422, filed September 3, 1927. The invention to which this divisional application is directed consists in an apparatus for impelling fluid in a conduit by intermittent pressure impulses, and consists in the elements and features of construction shown and described as indicated in the claim.

In the drawings:

Figure 1 is a vertical section of an impulser made in accordance with my invention.

Figure 2 is a section through the same.

Figure 3 is a view corresponding to the upper part of Figure 1 showing the parts'with the piston stem and operating connections in the position occupied on the completion of the fuel feeding stroke under conditions of low engine requirement of fuel.

Referring to Figure 1, the impulses for the device are supplied through a pipe, 31, which leads through an inclined port, 31, positioned at the lower side of the piston chamber, 32, so as to drain oil from said piston chamber, 32, liquid which may pass the piston, 33, said piston reciprocating in said piston chamber being arranged to provide air impulses through said pipe, 31. The piston, 33, has a number of air ports, 34, passing through the wall of the same, and a piston ring packing, 35, between the location of said ports and the head of the piston.

At the upper end of the stroke of the piston head, the vacuum in the cylinder below the piston is vented through the ports, 36, in the wall of the cylinder and at the lower end of the piston stroke the vacuum in the cylinder above the piston becomes vented through said ports, 36, registering with the port, 34, in the piston wall. The piston, 33, has a connecting rod, 37, which slidably passes through one arm of a rocker lever 38, carried by journal-bearings, 39, and having a roller, 40, at the end of the other arm and arranged to ride on a cam, 41, carried by a cam shaft, 42, driven from any suitable part of the engine, 4. The-extreme upper end of the connecting rod, 37, is provided with a bumper, 45, having a cushioning spring, 43,, held in place by a ring, 44, secured to the end of the connecting rod. The'bu nper, 45, serves as a stop for encounter of the lever, 38, at the limit of the lost motion,''the purpose of which is hereinafter explained-of the lever with respect to the piston. The inner end of said rocker arm, 38, furthermore, is provided with extension springs, 46 and 4'7, in order to force the rocker arm, 38, at all times against the face of the cam, 41, the other ends of the springs, 46 and 4'7, being connected to a bracket, 48, forming a part of a frame, 49, which carries the journal-bearings, 39. Said frame, 49, furthermore, acts as a support for one end of a main spring, 50, the other end of which rests in an annular support, 51, carried by the piston, 33, around the connecting rod, 37. It will be noted from Figure 1 that the frame, 49, and the cylinder, 32, are secured by means of bolts, 52, to an engine casting, 53.

The lost motion between the lever, 38, and the piston hereinafter in the claims referred to as the fuel-impelling element, which is provided and accommodated by the sliding engagement of the lever, 38, with the piston stem, 3'7, is made necessary by reason of the principle and mode of operation of the apparatus, consisting in that the fuel-impelling movement is performed yie1ding ly under the reaction of the spring, 50, which is compressed for said reaction in the intake stroke, and reacts with a predetermined pressure on the fuel column extending to the carbureter fuel chamber, for maintaining a pressure therein predetermined for properly supplying the carbureter, of which the fuel chamber, it will be understood, is of customary construction for maintaining a governed levelof fuel for supplying engine requirement.

From the arrangement for this method of operation, it results that after the fuel line to the carbureter and the carbureter fuel chamber have once become filled, the fuel-impelling element being retracted positively to the limit of the intake stroke in each revolution of the engine cam, will be movedin the opposite direction for its fuel feeding stroke only to the extentthat the engine requirement has taken the fuel from the carbureter fuel chamber in the interval following the last feeding impulse of the fuel-impelling element. g

In case of low engine requirement, the feeding movement of the impelling element may be very short, and accordingly, the lever at its sliding engagement with the stemof the impelling element, will be withdrawn from the bumper stop, 45, a distance nearly equal to the full stroke which the cam is calculated to give it and said stem in the active phase of the cam.

Thus it will be seen that under conditions of low engine requirement, the fuel-impelling 'element,the piston, 33,will be limited in its movement to a short portion of its possible stroke from and back to its fully retracted position, being retracted positively for fuel intake by the positive actuation of the engine cam in each revolution of the latter.

The position of the parts under such conditions of low' engine requirement at the end 01 the feeding stroke is illustrated in Figure 3.

In the operation of my invention, the gasoline is fed by constantly recurring pressure impulses due to the reaction of the spring, 50, which produces the forcing or pumping stroke of the pisten, 33, the springs, 46 and 4'1, being provided merely to cause the lever, 48, to contact at all times with the cam, 41.

It is to be understood that as the impulser any other known type of impulse producing means may be used instead of a piston.

While I have described my invention above in detail; I wish it to be understood that many changes may be made therein without departing from the spirit of the same.

I claim: A fuel pump comprising a pump casing havin a pumping chamber therein; a reciprocable pumping member forming a movable wall of said pumping chamber, said casing having a cavity therein on the opposite side of said pumping member from said pumping chamber, said pump casing being adapted for mounting on an engine casing adjacent an aperture thereof, whereby said casing cavity is in communication with the interior of said engine casing, an operating stem secured to said pumping member adapted to protrude into said engine casing from said cavity, an operating lever plvotally supported by said pump casing intermediate its ends and adapted to be positioned entirely within said engine casing, said lever being in operative engagement with said stem at one end and adapted for cam actuation at its other end.

EDWARD A. ROCKWELL. 

